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Resins have enormous potential in the removal of naphthenic acids (NAs) from transformer oil due to their rich porosity and high mechanical and diversified functionality, whereas their poor adsorption capacity limits application. In this work, the polystyrene-diethylamine resin (PS-DEA-x) was prepared by grafting diethylamine (DEA) onto chloromethylated polystyrene (PS-Cl) resin to efficiently adsorb cyclopentane carboxylic acid from transformer oil for the first time. The characterization analysis results indicated that amine contents were significantly enhanced with the increase in DEA. Particularly, resin with a molar ratio of 1:5 depending on chloromethyl to DEA (PS-DEA-5) exhibited the highest amine contents and efficient adsorption of cyclopentane carboxylic acid (static adsorption capacity up to 110.0 mg/g), which was about 5 times higher than that of the pristine PS-Cl. The thermodynamic and kinetic studies showed that the adsorption behaviors could be well fitted to the Langmuir isotherm equation and pseudo-second-order rate equation. Moreover, it was found that 1 g of the PS-DEA-5 can decontaminate about 760 mL transformer oil to meet reuse standards by a continuous stream, indicating its potential application in industry.
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BACKGROUND: Pulmonary infections often lead to poor prognoses in patients with chronic obstructive pulmonary disease (COPD). Activin A and CD64 play crucial pathological roles in the development of COPD. AIM: To explore the bacterial spectrum via analysis of activing A levels, CD64 index, and related mechanisms in COPD patients complicated with pulmonary infection. METHODS: Between March 2015 and January 2018, a total of 85 patients with COPD, who also suffered from pulmonary infections, were enrolled in this study as the pulmonary infection group. In addition, a total of 96 COPD patients, without pulmonary infection, were selected as the control group. Sputum samples of patients in the pulmonary infection group were cultivated for bacterial identification prior to administration of antibiotics. The neutrophil CD64 index was measured using flow cytometry, serum activin A levels were detected via an enzyme-linked immunosorbent assay, and activin A, Smad3, TLR4, MyD88, and NFκB protein expression was analyzed by Western blotting. RESULTS: Gram-negative bacteria were identified in 57.65% of the sputum samples in the pulmonary infection group. The most prevalent Gram-negative species were Pseudomonas aeruginosa and Klebsiella pneumoniae. Conversely, Gram-positive bacteria were identified in 41.18% of the sputum samples in the pulmonary infection group. The most common Gram-positive species was Streptococcus pneumoniae. Fungi were identified in 1.17% of the sputum samples in the pulmonary infection group. The CD64 index was significantly higher in the pulmonary infection group (0.91 ± 0.38) than in the control group (0.23 ± 0.14, P < 0.001). The serum activin A levels were significantly higher in the pulmonary infection group (43.50 ± 5.22 ng/mL), compared to the control group (34.82 ± 4.16 ng/mL, P < 0.001). The relative expression levels of activin A, Smad3, TLR4, MyD88, and NFκB were all significantly higher in the pulmonary infection group, compared to the control group (all P < 0.001). CONCLUSION: Pulmonary infections in COPD patients are mainly caused by Streptococcus pneumoniae, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Pulmonary infections can significantly increase neutrophil CD64 index and serum levels of activin A, thereby activating the activin A/Smad3 signaling pathway, which may positively regulate the TLR4/MyD88/NFκB signaling pathway.
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Chromium based metal-organic framework (MIL-53(Cr)) has enormous potential in the removal of organic contaminants from aqueous solutions due to its outstanding water stability, whereas its poor adsorption capacity limits the application. In this study, La/LaF3-MIL-53(Cr) was successfully synthesized by taking the advantages of La doping and LaF3 encapsulation with one-step hydrothermal method. Diverse analysis tools were utilized to verify that La not only existed in the framework, but also was loaded in the pores in the form of LaF3. The adsorption experiment results demonstrated that 0.3-La/LaF3-MIL-53(Cr) exhibited significantly improved adsorption capacity by four times compared with the pristine MIL-53(Cr) material. XPS and FTIR revealed that the affinity of La to tetracycline was significantly stronger than that of Cr and the excellent dispersion of LaF3 in the material may also be the cause of the increase in adsorption capacity. This study described a simple method to combine two different forms of modification and the modified material was potential for tetracycline adsorption.
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Cromo , Estructuras Metalorgánicas , Adsorción , TetraciclinaRESUMEN
An efficient strategy (spontaneous deposition to enhance noble metal dispersity and core-shell confinement to inhibit noble metal sintering) is presented to synthesize highly active and thermally stable Ru/ZrO2@SiO2 catalysts for dichloroethane combustion.
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Although the mechanism of chronic migraine is still unclear, more and more studies have shown that mitochondrial dysfunction plays a possible role in migraine pathophysiology. Silent information regulator 1 (SIRT1) plays a vital role in mitochondrial dysfunction in many diseases. However, there is no research on the role of SIRT1 in mitochondrial dysfunction of chronic migraine. The aim of this study was to explore the role of SIRT1 in mitochondrial dysfunction in chronic migraine. A rat model was established through repeated dural infusions of inflammatory soup for 7 days to simulate chronic migraine attacks. Cutaneous hyperalgesia caused by the repeated infusions of inflammatory soup was detected using the von Frey test. Then, we detected SIRT1 expression in the trigeminal nucleus caudalis. To explore the effect of SIRT1 on mitochondrial dysfunction in chronic migraine rats, we examined whether SRT1720, an activator of SIRT1, altered mitochondrial dysfunction in chronic migraine rats. Repeated infusions of inflammatory soup resulted in cutaneous hyperalgesia accompanied by downregulation of SIRT1. SRT1720 significantly alleviated the cutaneous hyperalgesia induced by repeated infusions of inflammatory soup. Furthermore, activation of SIRT1 markedly increased the expression of peroxisome proliferator-activated receptor gamma-coactivator 1-alpha, transcription factor A, nuclear respiratory factor 1 and nuclear respiratory factor 2 mitochondrial DNA and increased the ATP content and mitochondrial membrane potential. Our results indicate that SIRT1 may have an effect on mitochondrial dysfunction in chronic migraine rats. Activation of SIRT1 has a protective effect on mitochondrial function in chronic migraine rats.
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Trastornos Migrañosos/genética , Mitocondrias/metabolismo , Neuronas/metabolismo , Sirtuina 1/genética , Núcleos del Trigémino/metabolismo , Animales , Western Blotting , ADN Mitocondrial/metabolismo , Trastornos Migrañosos/metabolismo , Mitocondrias/ultraestructura , Factor 1 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Neuronas/ultraestructura , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Ratas , Factores de Transcripción/metabolismo , Núcleos del Trigémino/citología , Núcleos del Trigémino/ultraestructura , Regulación hacia ArribaRESUMEN
At present, activated carbon (AC) derived from industrial wastes has a great practical significance. In this work, residue activated carbon (RAC) was successfully synthesized from catechol distillation residue by a simple activation process based on two steps. The optimized RAC (RAC-800, activated at 800 °C) had high specific surface area (1800 m2/g) and large total pore volume (0.91 cm3/g). RAC-800 portrayed the evident increase of the graphitic structure and possessed abundant functional groups. Catechol (CC), phthalic acid (PA) and dimethyl phthalate (DMP) were chosen as typical pollutant to investigate the effect of different functional groups on adsorption aromatic compounds, and the equilibrium adsorption capacity of RAC-800 for CC, PA and DMP was 221.5, 365.0 and 449.9 mg/g, respectively. The adsorption behaviors were systematically studied by the combination of kinetic and thermodynamic model. The adsorption process was dominated by the π-π interaction, assisted by hydrogen bonding, hydrophobic and electrostatic interactions. In addition, regeneration study showed that the adsorption capacity can still remain over 88.5% after five cycles. In total, fine chemical distillation residues are promising to turn into the precursor of activated carbon, which has potential to be used as a good adsorbent for removal of aromatic compounds.
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Carbón Orgánico , Contaminantes Químicos del Agua , Adsorción , Catecoles , Destilación , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/análisisRESUMEN
The simultaneous shaping and confinement of Cu-based MOP in alginate-SiO2 spheres significantly enhance the mechanical strength and leaching resistance of Cu-MOP. The resulting MOP-alginate-SiO2 is shown through chemical fixation of CO2 to exhibit improved product yield over the parent Cu-MOP and Cu-alginate-SiO2.
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The specific mechanism of migraine chronification remains unclear. We previously demonstrated that synaptic plasticity was associated with migraine chronification. EphB receptors and their ligands, ephrinBs, are considered to be key molecules regulating the synaptic plasticity of the central nervous system. However, whether they can promote the chronification of migraine by regulating synaptic plasticity is unknown. Therefore, we investigated the role of ephrinB/EphB signaling in chronic migraine (CM). Male Sprague-Dawley rats were used to construct a chronic migraine model by dural infusion of an inflammatory soup for 7â¯days. We used qPCR, western blot, and immunofluorescence to detect the mRNA and protein levels of EphB2 and ephrinB2. The paw withdrawal latency and paw withdrawal threshold were measured after lateral ventricle treatment with EphB1-Fc (an inhibitor of EphB receptor). Changes in synaptic plasticity were explored by examining synaptic-associated proteins by western blot, dendritic spines of neurons by Golgi-Cox staining, and synaptic ultrastructure by transmission electron microscopy. We found that the expression of EphB2 and ephrinB2 increased in CM. The administration of EphB1-Fc relieved hyperalgesia and changes in synaptic plasticity induced by CM. In addition, EphB1-Fc inhibited the upregulation of NR2B phosphorylation. These results indicate that ephrinB/EphB signaling may regulate synaptic plasticity in CM via NR2B phosphorylation, which suggests the novel idea that ephrinB/EphB signaling may be a target for the treatment of migraine chronification.
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Hiperalgesia/fisiopatología , Trastornos Migrañosos/metabolismo , Plasticidad Neuronal/fisiología , Receptores de la Familia Eph/metabolismo , Animales , Enfermedad Crónica , Hiperalgesia/metabolismo , Masculino , Trastornos Migrañosos/fisiopatología , Neuronas/metabolismo , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Transducción de Señal/fisiología , Médula Espinal/metabolismo , Médula Espinal/fisiopatologíaRESUMEN
Central sensitization is the potential pathogenesis of chronic migraine (CM) and is related to persistent neuronal hyperexcitability. Dysfunction of excitatory amino acid transporter 2 (EAAT2) leads to the accumulation of glutamate in the synaptic cleft, which may contribute to central sensitization by overactivating glutamate N-methyl-D-aspartate receptors and enhancing synaptic plasticity. However, the therapeutic potential of CM by targeting glutamate clearance remains largely unexplored. The purpose of this study was to investigate the role of EAAT2 in CM central sensitization and explore the effect of EAAT2 expression enhancer LDN-212320 in CM rats. The glutamate concentration was measured by high-performance liquid chromatography in a rat model of CM. Then, q-PCR and western blots were performed to detect EAAT2 expression, and the immunoreactivity of astrocytes was detected by immunofluorescence staining. To understand the effect of EAAT2 on central sensitization of CM, mechanical and thermal hyperalgesia and central sensitization-associated proteins were examined after administration of LDN-212320. In addition, the expression of synaptic-associated proteins was examined and Golgi-Cox staining was used to observe the dendritic spine density of trigeminal nucleus caudalis neurons. Also, the synaptic ultrastructure was observed by transmission electron microscope (TEM) to explore the changes of synaptic plasticity. In our study, elevated glutamate concentration and decreased EAAT2 expression were found in the trigeminal nucleus caudalis of CM rats, administration of LDN-212320 greatly up-regulated the protein expression of EAAT2, alleviated hyperalgesia, decreased the concentration of glutamate and the activation of astrocytes. Furthermore, reductions in calcitonin gene-related peptide, substance P(SP), and phosphorylated NR2B were examined after administration of LDN-212320. Moreover evaluation of the synaptic structure, synaptic plasticity-, and central sensitization-related proteins indicated that EAAT2 might participate in the CM central sensitization process by regulating synaptic plasticity. Taken together, up-regulation of EAAT2 expression has a protective effect in CM rats, and LDN-212320 may have clinical therapeutic potential. Cover Image for this issue: https://doi.org/10.1111/jnc.14769.
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Astrocitos/metabolismo , Modelos Animales de Enfermedad , Transportador 2 de Aminoácidos Excitadores/biosíntesis , Trastornos Migrañosos/metabolismo , Regulación hacia Arriba/fisiología , Animales , Enfermedad Crónica , Craneotomía/efectos adversos , Craneotomía/métodos , Mediadores de Inflamación/efectos adversos , Mediadores de Inflamación/metabolismo , Masculino , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/etiología , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Piridazinas/farmacología , Piridazinas/uso terapéutico , Piridinas/farmacología , Piridinas/uso terapéutico , Distribución Aleatoria , Ratas , Ratas Sprague-DawleyRESUMEN
A novel two-stage fluidized-bed/fixed-bed catalytic system was developed for the treatment of benzaldehyde residue. The effects of reaction temperature, oxygen concentration, space velocity on the purification of benzaldehyde production residue were investigated. The effluent chemical oxygen demand (COD) was less than 70â mgO2/L and the COD removal efficiency was higher than 99.83% under our experimental condition (fluidized-bed and fixed-bed temperature of 300-400°C, the flow rate of residue of 10â mL/h and O2 excessive rate of 20). The volatile organic compounds (VOCs) of the outlet were not detected after the treatment. The high-efficiency performance of the process can last for at least 600â h in the stability experiment. It was also verified by gas chromatography-mass spectrometry (GC-MS) analysis that most organic pollutants in the residue were significantly removed after treatment. These results suggest that the two-stage fluidized-bed/fixed-bed catalytic system could be a promising technology for the dispose of chlorine-containing polymer organics in the chemical industry.
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Benzaldehídos , Reactores Biológicos , Análisis de la Demanda Biológica de Oxígeno , Catálisis , Temperatura , Eliminación de Residuos LíquidosRESUMEN
The fine-tuning of metal-based molecular building blocks in Zn-MOF-74 through post-synthetic cation exchange with Ca2+ significantly enhances its basicity and corresponding catalytic performance. The resulting material, exemplified by Ca/Zn-MOF-74, is shown through Knoevenagel condensation to give an improved product yield over the parent Zn-MOF-74 and Ni/Zn-MOF-74.
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Catalytic oxidation can efficiently eliminate nitrogen-containing volatile organic compounds (NVOCs) and suppress the generation of toxic NO x in order to avoid secondary pollution. In this study, mesoporous SiO2-confined LaMnO3 perovskite nanoparticles with high dispersion were successfully prepared by a citric acid-assisted deposition method (LMO/SiO2-SD) and tested for the oxidation of n-butylamine. The method utilized the synergistic effect of abundant active hydroxyl groups existing on the SiO2 gel surface and citric acid, rendering the metal ions more uniformly scattered on the SiO2 surface. Strikingly, the LMO/SiO2-SD sample exhibited the optimum catalytic performance (T 90 at 246 °C) and the highest N2 selectivity, which was mainly ascribed to its abundant surface acid sites, superior low-temperature reducibility and higher ratio of surface Mn4+ species. The apparent activation energy (E a) for n-butylamine oxidation over LMO/SiO2-SD sample was 29.0 kJ mol-1. Furthermore, the reaction mechanism of n-butylamine oxidation was investigated by in situ FITR and a reasonable reaction route for n-butylamine oxidation over the LMO/SiO2-SD sample was proposed.
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Solid base catalysts featuring green, robustness, and high activity play an important role in the current fine-chemical and petrochemical industry. Normally, the generation of supported K2O by thermal decomposition of KNO3 requires high temperature, and this process can sometimes destroy the structure of supporting materials. We herein report a solvent-assisted stepwise redox (SASR) approach to generate zeolite NaA-supported K2O, which we call K2O/NaA, that function as the solid base catalyst for Michael addition reaction between ethanol and ethyl acrylate. The solvent-assisted redox decomposition process of KNO3 at elevated temperature was investigated by thermogravimetry-mass spectrometry. It reveals that after reducing a minor amount of KNO3 at 400 °C, the organic solvent decomposes to form carbon, which promotes the reduction of KNO3 to generate strong basicity on the zeolite NaA at 600 °C. The resulting material, K2O/NaA-S, exhibits improved catalytic activity in Michael addition reaction over other benchmark base catalysts that have been used in this reaction. This catalyst is durable for at least four catalytic cycles without apparent loss in activity. K2O/NaA-S exhibits larger reaction rate constant yet lower activation energy than K2O/NaA prepared by thermal decomposition method. The SASR approach described in this paper represents a new blueprint for the generation of the supported alkali oxide as the solid base catalyst.
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Gold nanoparticles (3-4â nm) were deposited on Mn3O4 nanocrystallites with three distinct morphologies (cubic, hexagonal, and octahedral). The resulting structures were characterized, and their activities for benzene combustion were evaluated. The dominant exposed facets for the three kinds of Mn3O4 polyhedrons show the activity order: (103)≈(200)>(101). A similar activity order was derived for the interfaces between the Au and the Mn3O4 facet: Au/(200)≈Au/(103)>Au/(101). The metal-support interactions between the Au nanoclusters and specific facets of the Mn3O4 polyhedrons lead to a unique interfacial synergism in which the electronic modification of the Au nanoparticles and the morphology of the Mn3O4 substrate have a joint effect that is responsible for a significant enhancement in the catalytic activity of the Au/Mn3O4 system.
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We reported the morphology-directed synthesis of Co(3)O(4) nanotubes via interfacial reaction of NaOH with pre-fabricated CoC(2)O(4)·2H(2)O nanorods based on modified Kirkendall effect. The as-obtained Co(3)O(4) nanotubes showed excellent activity and durability in catalytic combustion of CH(4).